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The goals of the styrene oxide adsorption experiments were to develop reliable isotherms of styrene oxide onto Dowex Optipore L-493 resin and onto mesoporous carbon adsorbents, in addition to determining the ideal conditions for styrene oxide production from E. coli. Adsorption is an effective means of separation used in industry

The goals of the styrene oxide adsorption experiments were to develop reliable isotherms of styrene oxide onto Dowex Optipore L-493 resin and onto mesoporous carbon adsorbents, in addition to determining the ideal conditions for styrene oxide production from E. coli. Adsorption is an effective means of separation used in industry to separate compounds, often organics from air and water. Styrene oxide adsorption runs without E. coli were conducted at concentrations ranging from 0.15 to 3.00 g/L with resin masses ranging from 0.1 to 0.5 g of Dowex Optipore L-493 and 0.5 to 0.75 g of mesoporous carbon adsorbent. Runs were conducted on a shake plate operating at 80 rpm for 24 hours at ambient temperature. Isotherms were developed from the results and then adsorption experiments with E. coli and L-493 were performed. Runs were conducted at glucose concentrations ranging from 20-40 g/L and resin masses of 0.100 g to 0.800 g. Samples were incubated for 72 hours and styrene oxide production was measured using an HPLC device. Specific loading values reached up to 0.356 g/g for runs without E. coli and nearly 0.003 g of styrene oxide was adsorbed by L-493 during runs with E. coli. Styrene oxide production was most effective at low resin masses and medium glucose concentrations when produced by E. coli.
ContributorsHsu, Joshua (Co-author) / Oremland, Zachary (Co-author) / Nielsen, David (Thesis director) / Staggs, Kyle (Committee member) / Barrett, The Honors College (Contributor) / Chemical Engineering Program (Contributor) / School of Sustainability (Contributor)
Created2014-05
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Description
This study details the construction and operation of a dry-jet wet spinning apparatus for extruding hollow fiber membranes (HFMs). The main components of the apparatus are a spinneret, a coagulation bath, and an automatic collection reel. Continuous fiber formation was achieved using two syringe pumps simultaneously delivering polymer dope and

This study details the construction and operation of a dry-jet wet spinning apparatus for extruding hollow fiber membranes (HFMs). The main components of the apparatus are a spinneret, a coagulation bath, and an automatic collection reel. Continuous fiber formation was achieved using two syringe pumps simultaneously delivering polymer dope and bore fluid to the spinneret. Based on apparatus runs performed with Polysulfone (PSF) dopes dissolved in N,N-Dimethylacetamide and supporting rheological analysis, the entanglement concentration, ce, was identified as a minimum processing threshold for creating HFMs. Similarly, significant increases in the ultimate tensile strength, fracture strain, and Young's modulus for extruded HFMs were observed as polymer dope concentration was increased at levels near ce. Beyond this initial increase, subsequent tests at higher PSF concentrations yielded diminishing changes in mechanical properties, suggesting an asymptotic approach to a point where the trend would cease. Without further research, it is theorized that this point falls on a transition from the semidiute entangled to concentrated concentration regimes. SEM imaging of samples revealed the formation of grooved structures on the inner surface of samples, which was determined to be a result of the low flowrate and polymer dope concentrations used in processing the HFMs during apparatus runs. Based on continued operation of the preliminary apparatus design, many areas of improvement were noted. Namely, these consisted of controlling the collector speed, eliminating rubbing of nascent fibers against the edge of the coagulation bath by installing an elevated roller, and replacing tygon tubing for the polymer line with a luer lock adapter for direct syringe attachment to the spinneret.
ContributorsBridge, Alexander Thomas (Author) / Green, Matthew D. (Thesis director) / Lin, Jerry Y. S. (Committee member) / School of Mathematical and Statistical Sciences (Contributor) / Chemical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
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Description
Metal-organic frameworks (MOFs) are a new set of porous materials comprised of metals or metal clusters bonded together in a coordination system by organic linkers. They are becoming popular for gas separations due to their abilities to be tailored toward specific applications. Zirconium MOFs in particular are known for their

Metal-organic frameworks (MOFs) are a new set of porous materials comprised of metals or metal clusters bonded together in a coordination system by organic linkers. They are becoming popular for gas separations due to their abilities to be tailored toward specific applications. Zirconium MOFs in particular are known for their high stability under standard temperature and pressure due to the strength of the Zirconium-Oxygen coordination bond. However, the acid modulator needed to ensure long range order of the product also prevents complete linker deprotonation. This leads to a powder product that cannot easily be incorporated into continuous MOF membranes. This study therefore implemented a new bi-phase synthesis technique with a deprotonating agent to achieve intergrowth in UiO-66 membranes. Crystal intergrowth will allow for effective gas separations and future permeation testing. During experimentation, successful intergrown UiO-66 membranes were synthesized and characterized. The degree of intergrowth and crystal orientations varied with changing deprotonating agent concentration, modulator concentration, and ligand:modulator ratios. Further studies will focus on achieving the same results on porous substrates.
ContributorsClose, Emily Charlotte (Author) / Mu, Bin (Thesis director) / Shan, Bohan (Committee member) / Chemical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
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Description
Buried under ice and snow in Greenland, the abandoned Camp Century holds the remnants of a Danish-American Cold War-era operation left to achieve final disposal beneath a tomb of ice. Nearly 50 years later, climate projections hypothesize that snowmelt will exceed snowfall in 2090—releasing the trapped hazardous wastes at Cam

Buried under ice and snow in Greenland, the abandoned Camp Century holds the remnants of a Danish-American Cold War-era operation left to achieve final disposal beneath a tomb of ice. Nearly 50 years later, climate projections hypothesize that snowmelt will exceed snowfall in 2090—releasing the trapped hazardous wastes at Camp Century. This thesis examines the mechanisms through which the international community is able to remediate climate change impacts on Camp Century wastes. The wastes are characterized and examined as either a problem of transboundary pollution, as an issue of military accountability, or as an issue of climate change policy. As revealed, the wastes are unable to be classified as transboundary pollutants. Though classified as a point-source transboundary risk, they are neither a traded or public risk. Furthermore, no international or domestic transboundary pollution agreements incorporate provisions encompassing the specific attributes of Camp Century’s waste. Camp Century is also not an issue of military accountability as U.S. base cleanup laws and environmental regulations do not apply abroad and as the original bilateral agreement governing the site is insufficient in addressing potential ice melt. Finally, as examined through institutions such as the UNFCCC and the Paris Agreement, Camp Century is, again, unable to be incorporated in current frameworks such as adaptation as adaption efforts are concentrated on developing nations. This thesis reveals the inability of current frameworks, institutions, and agreements to effectively remediate Camp Century wastes which is a case utilized as a microcosm through which to examine international capacity in addressing climate-change induced impacts.
ContributorsKilker, Natalie Angelina (Author) / Klinsky, Sonja (Thesis director) / Bodansky, Daniel (Committee member) / School of Sustainability (Contributor) / School of Politics and Global Studies (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description

To mitigate climate change, carbon needs to be removed from the atmosphere and stored for thousands of years. Currently, carbon removal and storage are voluntarily procured, and longevity of storage is inconsistently defined and regulated. Clauses can be added to procurement contracts to require long-term management and increase the durability

To mitigate climate change, carbon needs to be removed from the atmosphere and stored for thousands of years. Currently, carbon removal and storage are voluntarily procured, and longevity of storage is inconsistently defined and regulated. Clauses can be added to procurement contracts to require long-term management and increase the durability of storage. Well-designed and properly enforced contracts can pave the way to future regulation for long-term carbon management.

ContributorsHagood, Emily (Author) / Lackner, Klaus (Thesis director) / Marchant, Gary (Committee member) / Barrett, The Honors College (Contributor) / Materials Science and Engineering Program (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / School of Sustainability (Contributor)
Created2023-05
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Description

Climate change is impacting fisheries through ecological shifts altering the geographical distribution and quantity of fish species. About 60% of United States fish caught by volume is caught in the Alaska region, with Alaska's economy dependent on fisheries. Additionally, fisheries are an important source of employment for many Alaskan communities.

Climate change is impacting fisheries through ecological shifts altering the geographical distribution and quantity of fish species. About 60% of United States fish caught by volume is caught in the Alaska region, with Alaska's economy dependent on fisheries. Additionally, fisheries are an important source of employment for many Alaskan communities. Therefore, it is important to have policies and strategies in place to prepare for ongoing climate impacts. One step to support better tailoring policy to support those most likely to be negatively impacted is to identify the fishing communities most vulnerable to climate change. This study uses data on vulnerable fish species and fishery catch by species and community to identify what communities are most vulnerable to changing climate conditions. I identify 26 communities that are fishing climate vulnerable species. I then use vulnerable fish species revenue data to identify communities most at risk either because they generate a substantial amount of revenue from these species or a substantial proportion of their total revenue is derived from these species. Using species-specific revenue, I show that Sablefish contribute the most to this vulnerability.

ContributorsFulton, Breanna (Author) / Kroetz, Kailin (Thesis director) / Abbot, Joshua (Committee member) / Barrett, The Honors College (Contributor) / School of Sustainability (Contributor) / School of Geographical Sciences and Urban Planning (Contributor)
Created2023-05
Description

This thesis will examine possible connection points between the health of a local environmental/climate news ecosystem and that local community’s belief in and vulnerability to the effects of climate change in Central Appalachia and Northern Virginia. The three counties that will be studied in Virginia are Arlington, Buchanan and Wise

This thesis will examine possible connection points between the health of a local environmental/climate news ecosystem and that local community’s belief in and vulnerability to the effects of climate change in Central Appalachia and Northern Virginia. The three counties that will be studied in Virginia are Arlington, Buchanan and Wise Counties. This research will be mainly a hypothesis-generating descriptive analysis of data, coupled with both interviews with researchers and local experts, in addition to observations from relevant literature about the possible connections between availability of environmental news with climate change, institutional belief and climate vulnerability data. The local history of resource extraction will also be explored. The point of this thesis is not to prove that a lack of access to strong, locally focused climate and environmental news increases vulnerability to the effects of climate change (although it does raise this as a possibility). Rather, it is to continue a conversation with journalists, media professionals and climate professionals about how to approach understanding and engaging groups left out of the climate conversation and groups who've been traditionally underserved by news media when it comes to climate information and appeals for institutional trust. This conversation is already happening, especially when it comes to the importance of the health of local, community focused news in general in Appalachia, but given the urgency and scale of the climate crisis, merits continuation and some inquiry into environmental news.

ContributorsFlaherty, Fiona (Author) / Beschloss, Steven (Thesis director) / Nelson, Jacob (Committee member) / Babits, Sadie (Committee member) / Barrett, The Honors College (Contributor) / School of Sustainability (Contributor) / Walter Cronkite School of Journalism and Mass Comm (Contributor) / School of International Letters and Cultures (Contributor)
Created2022-12
Description

This paper focuses on the impacts of climate change on the Two-Spirit, Lesbian, Gay, Bisexual, Transgender, Queer and/or Questioning, Intersex, Asexual (2SLGBTQIA+) population. The paper seeks to fill in the current gap within research in this particular area. I utilize a decolonial and intersectional framework to determine how to achieve

This paper focuses on the impacts of climate change on the Two-Spirit, Lesbian, Gay, Bisexual, Transgender, Queer and/or Questioning, Intersex, Asexual (2SLGBTQIA+) population. The paper seeks to fill in the current gap within research in this particular area. I utilize a decolonial and intersectional framework to determine how to achieve queer climate justice. In doing so, I conduct interviews with different climate activists and review current research to come up with possible responses.

ContributorsPrasad, Danielle (Author) / Silova, Iveta (Thesis director) / Barca, Lisa (Committee member) / Barrett, The Honors College (Contributor) / School of Social Transformation (Contributor) / School of Sustainability (Contributor)
Created2023-05
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Description
The purpose of this thesis is to imagine and predict the ways in which humans will utilize technology to feed the world population in the 21st century, in spite of significant challenges we have not faced before. This project will first thoroughly identify and explain the most pressing challenges the

The purpose of this thesis is to imagine and predict the ways in which humans will utilize technology to feed the world population in the 21st century, in spite of significant challenges we have not faced before. This project will first thoroughly identify and explain the most pressing challenges the future will bring in climate change and population growth; both projected to worsen as time goes on. To guide the prediction of how technology will impact the 21st century, a theoretical framework will be established, based upon the green revolution of the 20th century. The theoretical framework will summarize this important historical event, and analyze current thought concerning the socio-economic impacts of the agricultural technologies introduced during this time. Special attention will be paid to the unequal disbursement of benefits of this green revolution, and particularly how it affected small rural farmers. Analysis of the technologies introduced during the green revolution will be used to predict how 21st century technologies will further shape the agricultural sector. Then, the world’s current food crisis will be compared to the crisis that preceded the green revolution. A “second green revolution” is predicted, and the agricultural/economic impact of these advances is theorized based upon analysis of farming advances in the 20th century.
ContributorsWilson, Joshua J (Author) / Strumsky, Deborah (Thesis director) / Benjamin, Victor (Committee member) / Department of Supply Chain Management (Contributor) / School of Sustainability (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
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Description
Anthropogenic climate change caused by increasing carbon emissions poses a threat to nearly every living organism. One consequence of these emissions is ocean acidification (OA). While OA has been shown to directly inhibit growth in calcifying animals, it might also have negative effects on other marine life. I conducted a

Anthropogenic climate change caused by increasing carbon emissions poses a threat to nearly every living organism. One consequence of these emissions is ocean acidification (OA). While OA has been shown to directly inhibit growth in calcifying animals, it might also have negative effects on other marine life. I conducted a systematic quantitative literature review on the effects of OA on fish behavior. The review consisted of 29 peer-reviewed, published journal articles. Most articles report some degree of negative impact of OA. Impacts include sensory impairment, erratic swimming patterns and attraction to predators. Many studies report insignificant impacts, thus continued research is needed to understand the consequences of human behavior and assist in mitigating our impact.
ContributorsKubiak, Allison Noelle (Co-author) / Kubiak, Allison (Co-author) / Gerber, Leah (Thesis director) / Eikenberry, Steffen (Committee member) / Kelman, Jonathan (Committee member) / School of Sustainability (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05